透過遮罩、加長的噴嘴以及流量的調整改善微米粒子在平面上沉積的穩定性與均勻性

Abstract

本篇是針對固態粒子合成胜肽陣列法的製程改善之研究。此方法需要用高壓氣流灌入一個裝有大量生化合成用固態粒子(bio-particle)的容器，氣流衝擊固態粒子團後產生空氣與固態粒子的氣懸膠體(aerosol)，由於氣懸膠體受到亂流的影響，使粒子在沉積基板表面上時，容易造成晶片不同區域上的粒子數量不均。此現象嚴重地影響所製造的胜肽微陣列之可靠度。本研究目標是改善晶片上的粒子數量不均現象，因此架設一套可產生氣懸膠體的實驗設備，使用碳粉粒子代替生化合成用固態粒子進行沉積實驗，配合數值模擬進行比較。在模擬方面，使用FLUENT進行不同噴嘴的流場模擬，再以實驗的方式驗證模擬結果。實驗結果方面，在施加不同氣流壓力與流量的實驗時，發現碳粉會因為ring vortex現象的影響產生環形的空白區域。因此我們使用mask限制碳粉的沉積區域。經實驗與模擬驗證，mask能有效降低ring vortex的影響。最後，在固定的流量下，壓力的變化會影響碳粉沉積的厚度，而壓力固定的情況下，流量才是影響ring vortex現象的主因。

This study is focus on improving the process of particle-based synthesis of peptide microarray with CMOS chip. In this method, high pressure stream is required for pouring into particle reservoir with a large number of bio-particles, and high pressure stream impact bio-particles to form aerosol. The turbulence of flow affects aerosol and then make particle depositing inhomogeneously on the chip surface. This phenomenon severely affects the reliability of the peptide microarrays. The research objective is to improve this phenomenon, so we build up a set of experimental system and replace bio-particle with carbon toner for doing deposition experiments. We use numerical simulations comparing with experimental results. In simulations, we use FLUENT to simulate the flow field of different nozzles, and then do experiments to verify the simulation results. In experimental results, when different pressure and flow rate are applied to experiments, it is found that carbon toner affected by ring vortex and formed a ring-shaped blank area. Therefore we use mask to restrict deposition area of particles. This is proved by experiments and simulation that mask effectively reduces the influences of ring vortex. Finally, the pressure affects the thickness of particle layer under the condition of fixed flow rate, and flow rate is the main condition for ring vortex phenomenon under the condition of fixed pressure.